Users may interact with each other in a messaging service, sending messages back and forth to each other in a text-based conversation between two or more users. A user may have a user account associated with them in the messaging service, the user account providing an online identity for the user, a destination for messages directed to the user, and generally coordinating the user's access to and use of the messaging service. A user may access the messaging service from a variety of endpoints, including mobile devices (e.g., cellphones), desktop computers, web browsers, specialized messaging applications, etc. A user may use the messaging service to exchange pictures.